Investigator

Hiroyuki Yamazaki

Hokkaido University Hospital, Gynecology

HYHiroyuki Yamazaki
Papers(2)
The prognosis of endo…Human papillomavirus …
Collaborators(6)
Junzo HamanishiKazuhiro TakeharaKeiichiro NakamuraKoji MatsumotoNoriomi MatsumuraTakuma Fujii
Institutions(7)
Hokkaido University京都大学 / Kyoto Universi…Shikoku Cancer CenterOkayama University Ho…Showa UniversityKindai UniversityFujita Health Univers…

Papers

The prognosis of endometrial cancers stratified with conventional risk factors and modified molecular classification

AbstractThis study aimed to validate the Proactive Molecular Risk Classifier for Endometrial Cancer, a modified version of The Cancer Genome Atlas, using data from 184 patients with endometrial cancer (median age: 57.5 years; median follow‐up period: 109 months) who had undergone radical surgery (including systemic lymphadenectomy) and subsequent adjuvant chemotherapy (patients with intermediate or high recurrence risk) from 2003 to 2015. Tissue microarrays were prepared from surgical specimens and classified using the conventional clinical risk classifier. Immunohistochemistry was used to detect mismatch repair proteins, L1 cell adhesion molecule, and p53. Direct sequencing was used to identify hotspot mutations in the polymerase‐epsilon gene. Forty‐five patients were identified as having high L1 cell adhesion molecule expression, 41 as low risk, 34 as mismatch repair‐deficient, 13 as polymerase‐epsilon gene‐mutated, five as having abnormal p53, and 46 as other. Patients were stratified into significantly different prognostic groups (p < 0.0001): favorable (low risk and polymerase‐epsilon gene‐mutated), intermediate (mismatch repair‐deficient and other), and unfavorable (high L1 cell adhesion molecule expression and abnormal p53) with 5‐year disease‐specific survival rates of 100%, 93.8%, and 75.1%, respectively (Kaplan–Meier method). The combination of conventional recurrent risk classification, sequencing for polymerase‐epsilon gene mutations and immunohistochemistry for L1 cell adhesion molecule, p53, and mismatch repair proteins can be used to determine the prognoses of patients with endometrial cancer.

Human papillomavirus vaccine impact on invasive cervical cancer in Japan: Preliminary results from cancer statistics and the MINT study

AbstractThe first prophylactic vaccine against human papillomavirus (HPV) 16 and HPV18 was licensed in Japan in 2009. HPV vaccine effectiveness against high‐grade cervical lesions has been demonstrated among young Japanese women, but evidence of its effects on invasive cervical cancer (ICC) is lacking. Using data from two different cancer registries, we compared recent trends of new ICC cases by age group using Poisson regression analysis. We also analyzed time trends in HPV16/18 prevalence among 1414 Japanese women aged <40 years newly diagnosed with ICC in the past decade. Based on the population‐based cancer registry, the incidence of ICC among young women aged 20–29 years showed a significant decline from 3.6 to 2.8 per 100 000 women‐years during 2016–2019, but no similar decline was observed for older age groups (p < 0.01). Similarly, using data from the gynecological cancer registry of the Japan Society of Obstetrics and Gynecology, the annual number of ICCs among women aged 20–29 years also decreased from 256 cases to 135 cases during 2011–2020 (p < 0.0001). Furthermore, a declining trend in HPV16/18 prevalence in ICC was observed only among women aged 20–29 years during 2017–2022 (90.5%–64.7%, p = 0.05; Cochran–Armitage trend test). This is the first report to suggest population‐level effects of HPV vaccination on ICC in Japan. Although the declining trend in HPV16/18 prevalence among young women with ICC supports a causal linkage between vaccination and results from cancer registries, further studies are warranted to confirm that our findings are attributable to vaccination.

8Works
2Papers
6Collaborators

Positions

2020–

Researcher

Hokkaido University Hospital · Gynecology

Education

2033

PhD

Hokkaido University · Obstetrics and Gynecology

2010

MD

Hokkaido University

Country

JP

Links & IDs
0000-0001-8759-9607

Researcher Id: ABS-2876-2022